Tiles have been used to cover different surfaces for a long time. They are used in different environments to provide different functions, for example as a hard wearing surface, decoration or water proofing. The size, shape, material and surface finishing of each tile installed in a tiling array can all be varied according to the use requirements. A tiling array as defined herein is an array of tiles in various shapes, sizes and materials that fit together to continuously cover a surface.
One type of installation is where a surface is covered in a tiling array composed of the same general type of tile, although certain characteristics such as the colour and size may be varied to produce visually appealing decorative patterns. Precise alignment of the tiles is required to achieve the visual effect.
Another type of installation is where a tile is installed as a decorative insert in another floor covering array, such as hardwood flooring or parquets where adjacent flooring planks are connected together with an interlocking tongue and groove system. Currently it is difficult to install certain types of tile, such as stone or metal tiles, as decorative inserts because such types of tiles lack coupling regions.
Traditional tiles are typically affixed to surfaces by a labour-intensive method in which each tile is individually placed on the surface and affixed thereto using adhesive between an underside of the tile and the surface. This process is repeated until the surface is covered in an array of tiles. As these traditional tiles do not have an integral positioning mechanism, the alignment process depends on the skill of the installer, who can optionally use spacing inserts or other tools. Significant time, usually at least one day, is required to allow the adhesive to harden before any grout application process can start, such that the total time is at least 2 days. This has made the installation cost high for small jobs.
A further complication arises during installation because traditional tiles have significant dimensional variance: 2 mm is not unusual, and in some cases up to 5 mm. To accommodate the variance, installers have to leave space between the tiles. The gap between the tiles is filled in a manual labour-intensive process with a material known as grout, which hardens after application. The final appearance depends on the skill of the installer applying the grout, and installation by a non professional is tedious and prone to producing an unappealing finish. The composition of the grout is varied according to the use requirement, for example in wet environments the grout provides water proofing to prevent permeation of water to the underside of the tile. The grout is usually flexible enough to accommodate any thermal expansion.
If additional layers, such as cushioning or underlay layers, need to be installed then each tile will have to be connected to the layer, which further lengthens the installation process.
There is therefore a need to manufacture a tile which can be easily and quickly installed by a non-professional and which overcomes the above drawbacks.
Various attempts have been made to produce a tile which can be readily installed in a reduced amount of time, with minimal need for manual alignment of each tile.
One example is the Snapstone® tiling system (disclosed at www.snapstone.com) produced by the Snapstone Co. LLC. This utilizes a porcelain tile which is glued to a substrate having a push fit interlocking mechanism arranged along its edges which locks adjacent tiles together. After installing the Snapstone® tiles on a floor in a floating tile installation, the gaps between the interlocking tiles are filled with grout manually.
Although an improvement on traditional tiles, the Snapstone® tiling system is a partial solution because the installation process still requires the grouting step. Additionally, the Snapstone® tile also requires the use of adhesive to fasten the tile to the substrate. This is a significant drawback because the adhesive compound can fail in use, especially through moisture damage.
Another partial solution is disclosed in U.S. patent application Ser. No. 11/701,777, the contents of which are hereby incorporated by reference. A substrate which is formed in an injection moulding process, preferably Reaction Injection Moulding (“RIM”), is attached to a pre-formed tile to form a laminated groutless tile. The means of attachment is by bonding between the substrate and tile, such as by use of an adhesive. The edges of the substrate of the resulting laminate tile are then linear milled parallel to the edges of the tile to produce coupling members.
Manufacturing a tile using reaction injection moulding is relatively slow, taking between 10 and 20 minutes to make a single tile. Additionally, use of RIM results in the dimensions of the end product varying from the designed dimensions due to dimensional changes during curing. This and the material used result in any sealing effect with adjacent substrates being sub-optimal.
The process of milling after moulding disclosed in U.S. patent application Ser. No. 11/701,777 increases the manufacturing cost and time, wastes material and space, and places restrictions on the precision and types of coupling members that can be made.
In use, the tile of U.S. patent application Ser. No. 11/701,777 suffers from substrate-to-tile debonding due to failure of the adhesive.
The invention as claimed herein overcomes some or all of the above mentioned drawbacks and provides an improved method of manufacture with lower production cost.